1. Field of Invention
The present invention relates to a projection display device, and, more particularly, to a technique for efficiently cooling the component parts in the projection display device, using cooling air.
2. Description of Related Art
Hitherto, a projection display device has been known, which consists of a lamp serving as a light source, an optical system for optically treating light beams emitted from the lamp to form an optical image based on image information, a projection lens for projecting the image formed by the optical system onto a projection surface in enlarged form, and an electrical power supply for supplying electrical power to drive the projection display device.
Projection display devices of this type are used widely in multimedia presentations given, for example, at conferences, academic societies, or exhibitions.
Although such projection display devices may be installed in, for example, conference rooms where presentations are given, there may be times when they are brought in from or transferred to another place and stored there. Therefore, there is a need to make the projection display devices highly portable so that they can be easily carried around. This is achieved by making the projection display devices compact in size.
When projection display devices are made compact in size, the various component parts thereof are disposed close together in the projection display devices, making it harder for the cooling air drawn in by a fan or the like to circulate. Thus, how cooling paths are formed becomes important in achieving proper cooling of any heated component part.
Accordingly, it is an object of the present invention to provide a projection display device which can be more easily reduced in size and which can achieve proper cooling of the interior thereof.
According to the present invention, there is provided a projection display device consisting of a light source; an optical system including a light modulating system that modulates light beams emitted from the light source to form an optical image in accordance with image information; a projecting lens that projects the image formed by the optical system onto a projection surface in enlarged form; a power supply that supplies electrical power to drive the projection display device, the power supply consisting of a plurality of spaced apart power supply blocks; a plurality of power supply block cooling paths respectively formed at the power supply blocks that respectively cool the power supply blocks; and a light modulating system cooling path that cools the light modulating system.
In the projection display device, the power supply, which is relatively large compared to the other component parts, is formed so as to be divided into a plurality of power supply blocks, which can be efficiently disposed in the projection display device. Therefore, dead space is not easily formed in the projection display device, so that it can be reduced in size. In addition, although the power supply blocks and, in particular, the light modulating system of the optical system tends to generate heat compared to the other component parts, a cooling path is formed for each power supply block as well as for the light modulating system so that they can be properly cooled, resulting in more efficient cooling of the entire projection display device. By virtue of the invention, the above-described object is achieved.
In the projection display device of the present invention, the light modulating system consists of a plurality of light modulators.
In the projection display device of the present invention, a light source driver board that drives the light source may be disposed in at least one of the plurality of power supply block cooling paths; a control circuit board that controls the entire projection display device may be disposed in another one of the plurality of power supply block cooling paths; and a modulator driver board that drives the light modulators of the light modulating system may be disposed in the light modulating system cooling path.
In this case, a pair of the modulator driver boards may be disposed so as to be spaced apart, a space between the pair of modulator driver boards forming a part of the light modulating system cooling path.
In the projection display device of the present invention, the power supply block cooling paths and the light modulating system cooling path may be formed so as to pass by the light source.
In the aforementioned forms of the projection display device of the present invention, a plurality of exhaust fans disposed on different rotational axial lines may be provided to remove cooling air circulating in the plurality of power supply block cooling paths and the light modulating system cooling path, and a temperature sensor disposed in at least one of the power supply block cooling paths and the light modulating system cooling path may be provided to control the plurality of exhaust fans based on detection results obtained by of the temperature sensor.